They know that no one they arrest will be prosecuted. You'd maybe have action by federal law enforcement, however with the current administration that would be unlikely. I'd expect a massive stand down or walk off until there is a politician from governor all the way down to community organizer willing to prosecute to the full extent of the law.
Fiery but mostly peaceful! https://youtu.be/SGlvdc-iA5A?t=16
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